Parse harmony let declarations.

src/variables.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 23 matching lines @@
 namespace v8 {
 namespace internal {
 
 // ----------------------------------------------------------------------------
 // Implementation Variable.
 
 const char* Variable::Mode2String(Mode mode) {
   switch (mode) {
     case VAR: return "VAR";
     case CONST: return "CONST";
+    case LET: return "LET";
     case DYNAMIC: return "DYNAMIC";
     case DYNAMIC_GLOBAL: return "DYNAMIC_GLOBAL";
     case DYNAMIC_LOCAL: return "DYNAMIC_LOCAL";
     case INTERNAL: return "INTERNAL";
     case TEMPORARY: return "TEMPORARY";
   }
   UNREACHABLE();
   return NULL;
 }
 
@@ skipping 45 matching lines @@
 }
 
 
 bool Variable::is_global() const {
   // Temporaries are never global, they must always be allocated in the
   // activation frame.
   return mode_ != TEMPORARY && scope_ != NULL && scope_->is_global_scope();
 }
 
 } }  // namespace v8::internal